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《机械工程前沿（英文）》
2023年
第18卷
第1期
*doi:*
*10.1007/s11465-022-0727-x*

摘要：
High-entropy alloys (HEAs) are considered alternatives to traditional structural materials because of their superior mechanical, physical, and chemical properties. However, alloy composition combinations are too numerous to explore. Finding a rapid synthesis method to accelerate the development of HEA bulks is imperative. Existing *in situ* synthesis methods based on additive manufacturing are insufficient for efficiently controlling the uniformity and accuracy of components. In this work, laser powder bed fusion (L-PBF) is adopted for the *in situ* synthesis of equiatomic CoCrFeMnNi HEA from elemental powder mixtures. High composition accuracy is achieved in parallel with ensuring internal density. The L-PBF-based process parameters are optimized; and two different methods, namely, a multi-melting process and homogenization heat treatment, are adopted to address the problem of incompletely melted Cr particles in the single-melted samples. X-ray diffraction indicates that HEA microstructure can be obtained from elemental powders via L-PBF. In the triple-melted samples, a strong crystallographic texture can be observed through electron backscatter diffraction, with a maximum polar density of 9.92 and a high ultimate tensile strength (UTS) of (735.3 ± 14.1) MPa. The homogenization heat-treated samples appear more like coarse equiaxed grains, with a UTS of (650.8 ± 16.1) MPa and an elongation of (40.2% ± 1.3%). Cellular substructures are also observed in the triple-melted samples, but not in the homogenization heat-treated samples. The differences in mechanical properties primarily originate from the changes in strengthening mechanism. The even and flat fractographic morphologies of the homogenization heat-treated samples represent a more uniform internal microstructure that is different from the complex morphologies of the triple-melted samples. Relative to the multi-melted samples, the homogenization heat-treated samples exhibit better processability, with a smaller composition deviation, i.e., ≤ 0.32 at.%. The two methods presented in this study are expected to have considerable potential for developing HEAs with high composition accuracy and composition flexibility.

关键词：
laser powder bed fusion (L-PBF)
*in situ* alloying
high-entropy alloys
heat treatment
rapid synthesis

《能源前沿（英文）》
*doi:*
*10.1007/s11708-023-0892-6*

摘要：
High entropy materials (HEMs) have developed rapidly in the field of electrocatalytic water-electrolysis for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) due to their unique properties. In particular, HEM catalysts are composed of many elements. Therefore, they have rich active sites and enhanced entropy stability relative to single atoms. In this paper, the preparation strategies and applications of HEM catalysts in electrochemical water-electrolysis are reviewed to explore the stabilization of HEMs and their catalytic mechanisms as well as their application in support green hydrogen production. First, the concept and four characteristics of HEMs are introduced based on entropy and composition. Then, synthetic strategies of HEM catalysts are systematically reviewed in terms of the categories of bottom-up and top-down. The application of HEMs as catalysts for electrochemical water-electrolysis in recent years is emphatically discussed, and the mechanisms of improving the performance of electrocatalysis is expounded by combining theoretical calculation technology and *ex-situ*/*in situ* characterization experiments. Finally, the application prospect of HEMs is proposed to conquer the challenges in HEM catalyst fabrications and applications.

关键词： high-entropy electrocatalysis synthetic methods water-electrolysis hydrogen and oxygen evolutions

一种具有超高温工程应用潜力的氮化物增强NbMoTaWHfN难熔高熵合金 Article

万义兴, 程延海, Yongxiong Chen, Zhibin Zhang, Yanan Liu, Haijun Gong, Baolong Shen, Xiubing Liang

《工程（英文）》
2023年
第30卷
第11期
页码 110-120
*doi:*
*10.1016/j.eng.2023.06.008*

摘要：

Refractory high-entropy alloys (RHEAs) have promising applications as the new generation of high-temperature alloys in hypersonic vehicles, aero-engines, gas turbines, and nuclear power plants. This study focuses on the microstructures and mechanical properties of the NbMoTaW(HfN)* _{x}* (

关键词： Refractory high-entropy alloy High temperature Mechanical property Microstructure Strengthening mechanism

李天昕,王书道,卢一平,曹志强 ,王同敏,李廷举

《中国工程科学》
2023年
第25卷
第3期
页码 170-181
*doi:*
*10.15302/J-SSCAE-2023.03.016*

摘要：

随着世界科技水平的快速发展以及国民经济建设对高性能合金材料的迫切需求，传统单一主元合金逐渐不能满足人们与日俱增的使役需求。高熵合金因其独特的物理、化学以及力学性能，极大地拓展了金属材料成分设计范围，有望在国防、航空、航天、海洋、核能、医疗、新能源等重大工程领域发挥重要作用。本文结合各领域对先进高熵合金材料的具体需求，梳理了高熵合金材料的特征和内涵，分析了高熵合金材料发展的整体形势与前景，厘清了国内外高熵合金的发展现状。在此基础上，指出了我国高熵合金领域存在的差距和不足，我国高熵合金部分基础原材料依赖进口，严重威胁产业链安全；高熵合金产学研用体系尚未健全，工业化应用方面的研发投入有待提高。针对上述问题，研究建议，加强高熵合金材料研发的顶层设计，完善产业政策；加强企业和科研机构的对接和沟通；完善高熵合金材料标准、测试、表征、评价体系；推进人才队伍建设；降低材料成本，打造高附加值产品，促进我国先进高熵合金材料产业朝着体系化、绿色化、高端化、智能化方向发展。

High-order phase-field model with the local and second-order max-entropy approximants

Fatemeh AMIRI

《结构与土木工程前沿（英文）》
2019年
第13卷
第2期
页码 406-416
*doi:*
*10.1007/s11709-018-0475-5*

摘要：
We approximate the fracture surface energy functional based on phase-field method with smooth local maximum entropy (LME) and second-order maximum entropy (SME) approximants. The higher-order continuity of the meshfree methods such as LME and SME approximants allows to directly solve the fourth-order phase-field equations without splitting the fourth-order differential equation into two second-order differential equations. We will first show that the crack surface functional can be captured more accurately in the fourth-order model with smooth approximants such as LME, SME and B-spline. Furthermore, smaller length scale parameter is needed for the fourth-order model to approximate the energy functional. We also study SME approximants and drive the formulations. The proposed meshfree fourth-order phase-field formulation show more stable results for SME compared to LME meshfree methods.

关键词： second-order maximum entropy local maximum entropy second- and fourth-order phase-field models B-spline

Principle of maximum entropy for reliability analysis in the design of machine components

Yimin ZHANG

《机械工程前沿（英文）》
2019年
第14卷
第1期
页码 21-32
*doi:*
*10.1007/s11465-018-0512-z*

摘要：
We studied the reliability of machine components with parameters that follow an arbitrary statistical distribution using the principle of maximum entropy (PME). We used PME to select the statistical distribution that best fits the available information. We also established a probability density function (PDF) and a failure probability model for the parameters of mechanical components using the concept of entropy and the PME. We obtained the first four moments of the state function for reliability analysis and design. Furthermore, we attained an estimate of the PDF with the fewest human bias factors using the PME. This function was used to calculate the reliability of the machine components, including a connecting rod, a vehicle half-shaft, a front axle, a rear axle housing, and a leaf spring, which have parameters that typically follow a non-normal distribution. Simulations were conducted for comparison. This study provides a design methodology for the reliability of mechanical components for practical engineering projects.

关键词： machine components reliability arbitrary distribution parameter principle of maximum entropy

Maximum entropy based finite element analysis of porous media

Emad NOROUZI, Hesam MOSLEMZADEH, Soheil MOHAMMADI

《结构与土木工程前沿（英文）》
2019年
第13卷
第2期
页码 364-379
*doi:*
*10.1007/s11709-018-0470-x*

摘要：
The maximum entropy theory has been used in a wide variety of physical, mathematical and engineering applications in the past few years. However, its application in numerical methods, especially in developing new shape functions, has attracted much interest in recent years. These shape functions possess the potential for performing better than the conventional basis functions in problems with randomly generated coarse meshes. In this paper, the maximum entropy theory is adopted to spatially discretize the deformation variable of the governing coupled equations of porous media. This is in line with the well-known fact that higher-order shape functions can provide more stable solutions in porous problems. Some of the benchmark problems in deformable porous media are solved with the developed approach and the results are compared with available references.

关键词： maximum entropy FEM fully coupled multi-phase system porous media

Application of entropy-based fuzzy matter-element analysis in seepage monitoring of RCC dam

Chongshi GU, Zhijun ZHANG, Xin CAI, Yue HOU

《结构与土木工程前沿（英文）》
2011年
第5卷
第1期
页码 105-111
*doi:*
*10.1007/s11709-010-0015-4*

摘要：
Taking account of the fuzzy results of the seepage monitoring analysis of roller compacted concrete (RCC) dam and uncertainties of the individual indicator evaluation, the fuzzy matter-element model of seepage monitoring of RCC dam analysis has been established with the use of the fuzzy matter-element analysis theory and the concept of euclid approach degree. The use of entropy theory can calculate the weighting factor through the disorder utility values of the information reflected by the data itself, which can effectively avoid the problems of weight distribution and uncertainties of subjective judgments of the seepage monitoring analysis of roller compacted concrete dam. And further the example shows that the analysis of entropy-based fuzzy matter-element analysis model of the seepage monitoring of roller compacted concrete dam is in accordance with the actual situation, which verifies the effectiveness of the method.

关键词： information entropy fuzzy matter-element roller compacted concrete (RCC) dam seepage analysis

Optimization of cold-end system of thermal power plants based on entropy generation minimization

《能源前沿（英文）》
2022年
第16卷
第6期
页码 956-972
*doi:*
*10.1007/s11708-021-0785-5*

摘要：
Cold-end systems are heat sinks of thermal power cycles, which have an essential effect on the overall performance of thermal power plants. To enhance the efficiency of thermal power plants, multi-pressure condensers have been applied in some large-capacity thermal power plants. However, little attention has been paid to the optimization of the cold-end system with multi-pressure condensers which have multiple parameters to be identified. Therefore, the design optimization methods of cold-end systems with single- and multi-pressure condensers are developed based on the entropy generation rate, and the genetic algorithm (GA) is used to optimize multiple parameters. Multiple parameters, including heat transfer area of multi-pressure condensers, steam distribution in condensers, and cooling water mass flow rate, are optimized while considering detailed entropy generation rate of the cold-end systems. The results show that the entropy generation rate of the multi-pressure cold-end system is less than that of the single-pressure cold-end system when the total condenser area is constant. Moreover, the economic performance can be improved with the adoption of the multi-pressure cold-end system. When compared with the single-pressure cold-end system, the excess revenues gained by using dual- and quadruple-pressure cold-end systems are 575 and 580 k$/a, respectively.

关键词： cold-end system entropy generation minimization optimization economic analysis genetic algorithm (GA)

Zeshao CHEN, Songping MO, Peng HU, Shouli JIANG, Gang WANG, Xiaofang CHENG,

《能源前沿（英文）》
2010年
第4卷
第3期
页码 301-305
*doi:*
*10.1007/s11708-010-0006-0*

摘要：
Taking nonequilibrium radiative heat transfer between two surfaces as an example, the nonequilibrium thermodynamics of radiation is studied and discussed. The formulas of entropy flow, entropy generation, exergy flux, and optimal temperature of absorbing surface for maximum exergy output are derived. The result is a contribution to the thermodynamic analysis and optimization of solar energy utilization and can be applied in more complex radiative heat transfer cases.

关键词： radiative heat transfer entropy generation exergy thermodynamics

陈欣,和金生,董丽平

《中国工程科学》 2004年 第6卷 第12期 页码 43-46

摘要：

根据创新知识的形成受已有相关知识影响的假设，综合运用概率统计、最优化、最大熵原理构建了知识创新随机过程最大熵模型，给出了以已有知识x∈X为约束的新知识y∈Y的条件概率p(y|x)。模型具有随机性与因果性对立统一的特点。

罗党,刘思峰

《中国工程科学》 2004年 第6卷 第10期 页码 48-51

摘要：

以灰色系统理论和模糊数学为基础，探讨了不确定型决策问题的特性，分析了一些相关成果中所给方法在直接处理灰色模糊数方面的优势与不足。运用优化理论和熵极大化准则，建立了基于灰色模糊关系的多属性群体决策方法，分别对属性权重向量已知和未知两种情况给出了简便实用的算法，通过算例说明了算法的合理性。

邱菀华,谷晓燕

《中国工程科学》 2011年 第13卷 第8期 页码 73-79

摘要：

介绍了管理学、决策论和信息学的一个新交叉研究领域——工程管理熵学，从它诞生的必要性、科学性出发，进而阐述其理论基础、方法与模型，特别介绍了复熵决策法、群决策熵模型和多因素耦合决策熵方法，最后给出的工程管理应用案例表明，所提出的熵模型能够有效地解决实际工程管理中的决策难题。

Entropy production analysis of swirling diffusion combustion processes

Deodat MAKHANLALL, Linhua LIU,

《能源前沿（英文）》
2010年
第4卷
第3期
页码 326-332
*doi:*
*10.1007/s11708-009-0058-1*

摘要：
A critical factor in the design of combustion systems for optimum fuel economy and emission performance lies in adequately predicting thermodynamic irreversibilities associated with transport and chemical processes. The objective of this study is to map these irreversibilities in terms of entropy production for methane combustion. The numerical solution of the combustion process is conducted with the help of a Fluent 6.1.22 computer code, and the volumetric entropy production rate due to chemical reaction, viscous dissipation, and mass and heat transfer are calculated as post-processed quantities with the computed data of the reaction rates, fluid velocity, temperature and radiative intensity. This paper shows that radiative heat transfer, which is an important source of entropy production, cannot be omitted for combustion systems. The study is extended by conducting a parametric investigation to include the effects of wall emissivity, optical thickness, swirl number, and Boltzmann number on entropy production. Global entropy production rates decrease with the increase in swirl velocity, wall emissivity and optical thickness. Introducing swirling air into the combustion system and operations with the appropriate Boltzmann number reduces the irreversibility affected regions and improves energy utilization efficiency.

关键词： entropy-based design radiation transfer swirl magnussen combustion-model

标题 作者 时间 类型 操作

Rapid alloying of CoCrFeMnNi high-entropy alloy from elemental feedstock toward high-throughput synthesis

期刊论文

High-entropy catalysts for electrochemical water-electrolysis of hydrogen evolution and oxygen evolution

期刊论文

一种具有超高温工程应用潜力的氮化物增强NbMoTaWHfN难熔高熵合金

万义兴, 程延海, Yongxiong Chen, Zhibin Zhang, Yanan Liu, Haijun Gong, Baolong Shen, Xiubing Liang

期刊论文

High-order phase-field model with the local and second-order max-entropy approximants

Fatemeh AMIRI

期刊论文

Principle of maximum entropy for reliability analysis in the design of machine components

Yimin ZHANG

期刊论文

Maximum entropy based finite element analysis of porous media

Emad NOROUZI, Hesam MOSLEMZADEH, Soheil MOHAMMADI

期刊论文

Application of entropy-based fuzzy matter-element analysis in seepage monitoring of RCC dam

Chongshi GU, Zhijun ZHANG, Xin CAI, Yue HOU

期刊论文

Optimization of cold-end system of thermal power plants based on entropy generation minimization

期刊论文

Entropy flow, entropy generation, exergy flux, and optimal absorbing temperature in radiative transfer

Zeshao CHEN, Songping MO, Peng HU, Shouli JIANG, Gang WANG, Xiaofang CHENG,

期刊论文

Entropy production analysis of swirling diffusion combustion processes

Deodat MAKHANLALL, Linhua LIU,

期刊论文